Controlling device for punch-presses



W. J. PARKINSON.

CONTROLLING DEVICE FOR PUNCH PRESSES.

APPLICATION FILED OCT. 15. 1917.

1,348,580. Patented June 15, 1920.

; ATTOIgNEYS.

umrsnsmrsi PA TENT OF I 1 .WILLIAM J. PARKINSON, OF ROCHESTER, NEV YORK, -ASSIGNOR TO EASTMAN KODAK COMPANY, OF ROCHESTER, NEW YORK, A CORPORATION OF NEW Your;

oonrnonnnve DEVICE FOR rUNcH-rREssns.

Specification of Letters Patent. Patented J 11116 15 192() Application filed October 15, 1917. Serial No. 196,559.

I '0 all whom it may concern 7 Be it known that I, WILLIAM J. PARKIN- soN, of Rochester, in the county of Monroe and State of New York, have'invented certain new and useful Improvements in Controlling Devices for Punch-Presses; and I do hereby declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming a part of this specification, and to the reference-numerals marked thereon. I

My present invention relates to punch presses andmore particularly to safetyappliances therefor and it has for its object to provide a simple and'dependable device that can be relied upon to cause the disengagement of'the clutch and hence bring the ram to rest after each cycle of movement. A further object of the invention is to msure the return of the operating treadle by positively acting means after each cycle of operat on instead of dependingupon a spring or counterweight. To these and other ends the invention resides in certain improvements'and combinations of parts all as will be hereinafter more fully described, the novel features being pointed out in the claims at the end of the specification.

In the drawings: 7

Figure 1 is a side elevation, of a punch press constructed in accordance with and illustrating one embodiment of-1ny invention, a part of the driving wheel being broken away to show details of the safety device which latter is in normal position;

Fig. 2 is an enlarged fragmentary view of apart of the safety mechanism taken in section through the drive shaft and showing the positions of the parts as the clutch goes into engagement and L Fig. 3 is an enlarged fragmentary detail section taken substantially on the line 3--3 of Fig. 2. r i L I Similar reference numerals throughout the several views indicate the same parts.

In the present embodiment of the invention, 1 indicates the base; 2'the upper frame; 3 the bed, and 4 the ram of a punch press of a well known form. The ram operates in guides'o and is reciprocated by a crank and connecting rod (not shown) from a shaft 6 journaled in the top of the frame 2. Rotatable freely on a reduced portion 7 of the shaft is the driving pulley 8 and adjacent to it is a clutch hub 9 suitably fixed'to the shaft. A rocking clutch member 10 lies in a semi-cylindrical recess 11 in the shaft with its outer surface flush with the peripheryof the shaft. Said clutch member has a hearing at 12 for a cylindrical portion 13 thereof in the hub 9 while an arm '14 extends from the bearing radially of the shaft at theinner side of the hub. A recess 15 in the bearing portion ofthe drive wheel 8 passes over the clutch member 10 asthe wheel rotates and when pressure tending to tilt or cook the. member 10 is exerted, it will throw said cavity in the hub 9. The position of the arm 1 1 when the clutch member 10 is in operative position is'indicated by dotted lines in Fig. 2.

The clutch 10 is normally held inoperative against the tension of the spring 17 by a stop arm 19 pivoted at 29 to a bracket 21 on the frame 2. This position is shown in Fig. 1. A link 22 connectsithe stop-arm 19 with a rocker arm 23 which, in turn, is connected by a link 24: with the usual operating treadle 25 pivoted'at 26 to the base 1. Also connected to the rocker arm 23 at the rear of the machine is a counterweight 27 which connteracts the weight of this operating gear and the lower end of which I prefer to connect to the base 1 by'a spring 28 which assists it and also prevents it from swinging. This counterweight, acting through the link 22, also has a tendency to normally hold the stop arm 19 in operative position in the path of the clutch arm 14- so that the clutch is held out and the drive wheel 8 rotates freely on the shaft 6. r

In the operation of the device,each time the treadle 25 is depressed the stop arm 19 is withdrawn, the clutch arm 14 is released, as shown in Fig. 2, and the drive--ivheel 8 ereagalnst and adj netcarries the shaft 6 around one revolution or movement on its pivot bearing 20 to reduce V the shock'of theimpact as the clutch is arm 19 back into the path of the clutch arm 14: to prevent the latter from making more than one revolution and hence the ram 4 from making more than one reciprocation. In the present instance, this means embodies a safety arm 33 integral with the arm 19 and forming therewith a bell crank lever. When the arm 19 is thrown out as in Fig. 2 to re- 7 lease the clutch arm n and. cause the operation of the clutch, the arm 33 is correspondingly thrown in toward the center of rota tion and into the path of a cam 34 on hub 9 as shown in Fig. 2. It falls in rear. of the. cam which travels in the dlrectlon ofthe arrow and when the drive wheel and shaft have traveled together for one revolution,

the cam rocks the arm 33 back to its former position and hence the stop arm 19 is positively actuated back into the path of the clutch arm 14 to operate it and throw out the a clutch as in Fig; 1. The safety function consists in'the positive actuation of the arm I9 as distinguished from the further actuation thereof by the counterweight 27 and spring 28. The operator is led to expect a single operation of the ram 4 each time the treadle. is pressed andlience an immediate repetition. thereof is very apt to catch him off. his guard. and result in his serious injury. If the treadl e remains down for any reason, such a repetition would occur without the arm 33 even with the presence of the counterweight 27 and spring 28. Without pos-itively acting restoring means, no device can be called safe where springs or counterweights are relied upon. I

Aside from drawing the stop arm into the path of the clutch arm 14:, the arm 33 through links :22 and 2a raises the operating treadle 25. The treadle therefore cannot be held down during successive operations of the ram as it could were the arm 33 omitted and if it is the habit of the operator to let the weigh-t of his leg remain on thetreadle, the spring alone is not relied upon to-return the latter.

I claim as my invention:

1. In a punch press, the combination with a rotary shaft, of a driving wheel therefor, a clutch member rotatable with the shaft and having a normal tendency to operatively connect the driving wheel and shaft, a stop 19- ack arm mounted transversely to the shaft on a yieldable pivot, and normally engaged by the clutch member to release the same, a

safety arm .also arranged transversely to the arm at each revolution of the shaft to: move said stop arm into engagement with the clutch member, and cause said safety arm to be released from positive actuation after the stop arm has engaged theclutch-membjer.

2. In a punch press, the combination with v a rotary shaft, a rotaryv driving wheel and a clutch member having a normal tendency to connect the two for movement and rotata-ble with the shaft, of a -bell crank lever having a stop arm yieldably mounted normally in the path of the clutch. member to release the same, anda safety arm in a plane transverse to the shaft and in substantially the same plane as the stop arm for posi-- tively throwing." the. stop arm into the path 7 upon one of the rotary elements for. actuatingsaid safety arm when. in operative position, and an operating, member connected to release the stop arm and to positively move said safety arm to operative position.

3. In a punch press, the combination with a rotary shaft, a rotary driving wheel,'a cam onione of said elements and a clutch member having a normal tendency to connect the two elementsfor movement and rotatable with the shaft, of a stop normally in. the path of v the clutch member to release the same, an arm rigidly connected'to the stop and actuated by the cam for positively throwing the stop into the path of the clutch member, said arm being normally in inoperative position, and an operating member connected to simultaneously release the stop and positively move the arm to operative position in the path of the cam, said stop being engaged by the clutch member while the cam acts upon the arm connected to the stop.

4. In a punch press, the combination with a rotary shaft, a rotary driving wheel, a cam upon one of saidelements and a clutch member having a normal tendency to con nect the two for movement and movable therewith, of a bell crank lever adapted to rock in a plane transverse to the axis of the for reversing the: normal position of both arms thereof;

5. In a punch press, the combination with a rotary shaft, a rotary driving wheel and of the. clutch member, a device 90 a clutch member for connecting the two for gage said clutch member during its positive movement, of a foot treadle adapted to effect actuation.

the OperatiOIl Of the Clutch When depressed J and a device positively actuated upon each rotation of the shaft connected to eifect the Witnesses:

release of the clutch and to positively raise HELEN M. FRASER:

the foot treadle to initial position, and to en- MARGARET DUIGNAN. 

